P1258807537cqyhA

1
We piggybacked on Fleenors 2 August DWSC
experiments and obtained water samples every 2-4
hours from the houseboat, and low/high tide
samples from the traveling boats. Analyses
Nitrate d15N/d18O (done) POM d15N/d13C (in
progress) DOC-d13C (done) DIC-d13C (done) DO-d18O
(almost done) Water-d18O/d2H (not done
yet) Ammonium (archived)
2
(No Transcript)
3
48-Hour Diel Cycle of DO concentrations and d18O

• Typical pattern found in small lakes and streams
• 140 range in O2 saturation in 24 hours
• 17 range in d18O of DO over 24 hours

(are currently giving this a try at a few USGS
studies in CA, OR, WA)
(from Len Wassenaar, 2001)
4
How to tease out the main controls on DO levels
in the DWSC (and elsewhere) Photosynthesis
(P) Respiration (R) Nitrification (N)
R
N
d18O
P
DO
P
N
d13C
These processes will probably also cause
diagnostic changes in the d18O/d15N of nitrate
and the d15N/d13C of POM
R
DIC
5
(No Transcript)